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27
3P362438-5N English
14 .2 . Calculating the additional refrigerant charge
NOTE
The refrigerant charge of the system must be less than 210 lbs.
(100 kg). This means that in case the calculated total refrigerant
charge is equal to or more than 209 lbs. (95 kg) you must divide your
multiple outdoor system into smaller independent systems, each
containing less than 209 lbs. (95 kg) refrigerant charge. For factory
charge, refer to the unit nameplate.
14 .2 .1 . How to calculate the additional refrigerant to be charged
Additional refrigerant to be charged=R (lbs.). R should be rounded off
in units of 0.1 lbs.
R=[(X
1
×
f
7/8)
×
0.249+(X
2
×
f
3/4)
×
0.175+(X
3
×
f
5/8)
×
0.121+(X
4
×
f
1/2)
×
0.081+(X
5
×
f
3/8)
×
0.040+(X
6
×
f
1/4)
×
0.015]
×
1.04+[A]+[B]+[C]+[E]
X
1...6
=Total length (ft. (m)) of liquid piping size at
f
a
* In units of 0.1 kg, additional refrigerant to be charged=R (kg).
R=[(X
1
×
f
22.2)
×
0.37+(X
2
×
f
19.1)
×
0.26+(X
3
×
f
15.9)
×
0.18+(X
4
×
f
12.7)
×
0.12+(X
5
×
f
9.5)
×
0.059+(X
6
×
f
6.4)
×
0.022] × 1.04+[A]+[B]+[C]+[E]
Parameter [A]
Refrigerant amount for Branch Selector units
Branch Selector unit model
Refrigerant amount
BS4Q54T
0.7 lbs./unit (0.3 kg/unit)
BS6Q54T
0.9 lbs./unit (0.4 kg/unit)
BS8Q54T
1.1 lbs./unit (0.5 kg/unit)
BS10Q54T
1.5 lbs./unit (0.7 kg/unit)
BS12Q54T
1.8 lbs./unit (0.8 kg/unit)
BSQ36T
0.1 lbs./unit (0.05 kg/unit)
BSQ60T
0.2 lbs./unit (0.1 kg/unit)
BSQ96T
0.4 lbs./unit (0.2 kg/unit)
Parameter [B]
Refrigerant amount for outdoor units
Outdoor unit capacity type
Refrigerant amount
REYQ72T
0.0 lbs./unit (0.0 kg/unit)
REYQ96T
3.1 lbs./unit (1.4 kg/unit)
REYQ120T
3.3 lbs./unit (1.5 kg/unit)
REYQ144T
10.6 lbs./unit (4.8 kg/unit)
REYQ168T
10.8 lbs./unit (4.9 kg/unit)
Parameter [C]
Refrigerant amount by field piping length
and indoor units capacity
Field
piping
length
Total
indoor unit
capacity
connection
ratio
Refrigerant amount
Total outdoor unit capacity type
REYQ72-
144T
REYQ168-
288T
REYQ312-
456T
< 295.3 ft.
(90 m)
≤ 85%
0.0
>
85%
The smaller of [D]
or 5.51 lbs. (2.5 kg)
The smaller of [D]
or 6.61 lbs. (3.0 kg)
The smaller of [D]
or 7.50 lbs. (3.4 kg)
≥ 295.3 ft.
(90 m)
≤ 85%
0.0
>
85%
2.20 lbs. (1.0 kg)
Parameter [D]
Indoor unit
capacity
type
FXMQ type
07
09
12
15
18
24
30
36
48
54
Refrigerant
amount
(lbs. (kg)/unit)
0.06
(0.03)
0.03
(0.014)
0.14
(0.06)
0.29
(0.13)
0.25
(0.11)
0.16
(0.07)
0.33
(0.15)
0.25
(0.11)
0.08
(0.04)
0.00
(0.00)
Indoor unit
capacity
type
FXFQ type
Others
07
09
12
15
18
24
30
36
48
Refrigerant
amount
(lbs. (kg)/unit)
0.36
(0.16)
0.33
(0.15)
0.30
(0.14)
0.26
(0.12)
0.61
(0.28)
0.53
(0.24)
0.61
(0.28)
0.53
(0.24)
0.36
(0.16)
0.00
(0.00)
Parameter [E]
Refrigerant amount for DOAS
Refer to DOAS Installation Manual for additional refrigerant amounts
for DOAS connections
Example for refrigerant branch using REFNET joint and REFNET
header for systems and each pipe length as shown below. (Example
7.5. System piping (length) limitations on page 11.)
Outdoor system: REYQ264TATJ
*
(REYQ144TATJ
*
+REYQ120TATJ
*
)
Branch Selector units
BS4Q54T × 1, BSQ60T × 1, BSQ96T × 1
Indoor units
FXMQ type: 18 × 1, 24 × 2 , 36 × 1 , 54 × 1
FXFQ type: 36 × 2
Other: 48 × 1
Liquid piping
a:
f
3/4 × 60 ft.
e:
f
1/4
×
15 ft. i:
f
3/8
×
20 ft. m:
f
3/8
×
15 ft. r:
f
1/2
×
10 ft.
b:
f
5/8 × 20 ft.
f:
f
3/8
×
10 ft.
j:
f
3/8
×
10 ft. n:
f
3/8
×
15 ft.
t:
f
1/2
×
15 ft.
c:
f
1/2 × 10 ft.
g:
f
3/8
×
10 ft. k:
f
3/8
×
10 ft. o:
f
3/8
×
10 ft.
d:
f
3/8 × 15 ft.
h:
f
3/8
×
15 ft.
ℓ:
f
3/8
×
15 ft. p:
f
3/8
×
10 ft.
Total length of liquid piping: 285 ft.
Total capacity of indoor unit: 104.5%
[D]
=
0.25×1
+
0.16×2
+
0.25×1
+
0.00×1
+
0.53×2
+
0.00×1
= 1.88 lbs.
↑
FXMQ18x1
↑
FXMQ24x2
↑
FXMQ36x1
↑
FXMQ54x1
↑
FXFQ36x2
↑
Other48x1
[C]: The smaller of [D] or 6.61 lbs. = 1.88 lbs.
R = (
60×0.175
+
20×0.121
+
35×0.081
+
155×0.040
+
15×0.015
)
×
1.04 + 1.3 + 13.9 + 1.88
↑
a
↑
b
↑
c, r, t
↑
d, f, g, h, i,
j, k, ℓ, m,
n, o, p
↑
e
↑
[A]
↑
[B]
↑
[C]
= 40.1472
⇒
40.1 lbs.
Round off in units of 0.1 lbs.
INFORMATION
Piping length is considered the distance from the outdoor unit to the
farthest indoor unit.
01_EN_3P362438-5N.indb 27
12/11/2019 11:24:21 AM